“Border rancher: ‘We’ve found prayer rugs out here. It’s unreal.’ Washington Examiner People coming across the Southern Border from many countries, some of which would be a big surprise,” Trump tweeted Friday morning.

Rumors about prayer rugs at the border have circulated for more than a decade: In 2014, for example, Breitbart published a story that also cited a single anonymous source, without evidence, that they had also seen prayer rugs at the border. Fact-checkers have also debunked several politicians’ claims about border rugs at the southern border.

Trump frequently tries to link terrorism to border security, even though a goodamount of research conducted since 9/11 indicates that the principal terror threat to the U.S. is homegrown. Trump also often associates terrorism to Muslims. “Islam hates us,” Trump said in March 2016. Last year, Trump — without evidence, once again — pointed to group of migrants and asylum seekers traveling toward the U.S. border as a possible terrorists.

“I think there’s a very good chance you have people in there,” the president said in reference to terrorists, although he conceded there was “no proof of anything.”

The Trump administration has drastically inflated statistics on attempted border crossings made by known or suspected terrorists. Customs and Border Protection said in January that six people in terrorism databases were stopped at the southern border in the first half of fiscal year 2018. White House press secretary Sarah Huckabee Sanders, however, claimed that number was 4,000 in that entire fiscal year. Conversely, Customs and Border Protection said its agents stopped 91 people in the database on the U.S.’s northern border, 41 of whom were not American residents.

In 2017, the State Department also said that terrorist groups were more likely to access the U.S. through other means than through the southern border.